diff options
| -rw-r--r-- | src/SplitVector.h | 6 | ||||
| -rw-r--r-- | test/unit/testSplitVector.cxx | 21 |
2 files changed, 25 insertions, 2 deletions
diff --git a/src/SplitVector.h b/src/SplitVector.h index fcd8b0d0e..e805c50dc 100644 --- a/src/SplitVector.h +++ b/src/SplitVector.h @@ -206,11 +206,12 @@ public: /// Add some new empty elements. /// InsertValue is good for value objects but not for unique_ptr objects /// since they can only be moved from once. - void InsertEmpty(ptrdiff_t position, ptrdiff_t insertLength) { + /// Callers can write to the returned pointer to transform inputs without copies. + T *InsertEmpty(ptrdiff_t position, ptrdiff_t insertLength) { PLATFORM_ASSERT((position >= 0) && (position <= lengthBody)); if (insertLength > 0) { if ((position < 0) || (position > lengthBody)) { - return; + return nullptr; } RoomFor(insertLength); GapTo(position); @@ -222,6 +223,7 @@ public: part1Length += insertLength; gapLength -= insertLength; } + return body.data() + position; } /// Ensure at least length elements allocated, diff --git a/test/unit/testSplitVector.cxx b/test/unit/testSplitVector.cxx index a1426d38a..8a688cd5c 100644 --- a/test/unit/testSplitVector.cxx +++ b/test/unit/testSplitVector.cxx @@ -168,6 +168,27 @@ TEST_CASE("SplitVector") { } } + SECTION("InsertEmpty") { + sv.InsertEmpty(0, 0); + REQUIRE(0 == sv.Length()); + int *pi = sv.InsertEmpty(0, 2); + REQUIRE(2 == sv.Length()); + REQUIRE(0 == sv.ValueAt(0)); + REQUIRE(0 == sv.ValueAt(1)); + pi[0] = 4; + pi[1] = 5; + REQUIRE(4 == sv.ValueAt(0)); + REQUIRE(5 == sv.ValueAt(1)); + pi = sv.InsertEmpty(1, 2); + pi[0] = 6; + pi[1] = 7; + REQUIRE(4 == sv.Length()); + REQUIRE(4 == sv.ValueAt(0)); + REQUIRE(6 == sv.ValueAt(1)); + REQUIRE(7 == sv.ValueAt(2)); + REQUIRE(5 == sv.ValueAt(3)); + } + SECTION("SetValue") { sv.InsertValue(0, 10, 0); sv.SetValueAt(5, 3); |